Micro-Air Vehicles that Morph and Respond like Birds
Fixed wing aircrafts are usually designed to operate at peak performance for particular and limited operating conditions. Morphing wing aircrafts, on the other hand, have the potential to change their geometry and customize their performance to operate at peak levels in multiple flight modes and environments. Birds serve as a model for many morphing wing concepts, but very few examples of synthetic wings exist that mimic the musculoskeletal system of the animals or the somewhat mysterious ways in which birds use passive dynamics during flight.
Robert F. Shepherd, Mechanical and Aerospace Engineering, is developing materials that could allow micro-air vehicles to morph and respond more like birds. Previous attempts to design aircrafts with bird-like wings have had stiff, hinged structures that do not significantly change their shape. Shepherd’s group is creating composites with variable stiffness, made of phase-changing material embedded in stretchable elastomers. These composites offer a new material option to take advantage of passive dynamics and continuous deformation in morphing wings.
Shepherd’s three-dimensionally printed, high toughness elastomeric matrices will be embedded with phase-changing granules, co-continuous vascular networks for power and control, and distributed computation. His team is investigating methods of heating and cooling, as well as how to transfer power both directly and wirelessly. Ideally, the phase-changing network will be able to locally liquefy or solidify, rapidly, due to the microvascular network of heating and cooling elements. This research will contribute significantly to the pursuit of a large class of future autonomous materials that integrate sensing, actuation, computation, and communication.